The Hindu Business Line : `Efficacy' factor will be key to Glivec patent case

Thiruvananthapuram June 21 The Intellectual Property Appellate Board (IPAB), Chennai, will ascertain the `bio-availability' and, in turn, efficacy of `imatinib mesylate' - the chemical substance which is the active pharmaceutical ingredient in the drug developed by Novartis - to arrive at a decision in the company's patent case on the drug pending before it.

Imatinib mesylate is used in the marketed formulation of Novartis blockbuster anticancer drug Glivec.

Patentability

The "patentability" will depend on whether the IPAB is convinced that `imatinib mesylate' was 30 per cent more "bio-available" (a reference to the drug's capacity for absorption in the body) than other forms and, therefore, more "efficacious" to be eligible for patent protection said Mr R.S. Praveen Raj, an IP expert and a former Examiner with India Patent Office.

The case

Swiss drug maker Novartis challenged in the Madras high Court a decision, originally made by an Assistant Controller of Patents and Designs, rejecting a patent for beta-crystalline form of imatinib mesylate.

The court subsequently transferred the case to a Division Bench of IPAB comprising its Chairman, Mr Justice M.H.S. Ansari, and the technical member, Mr S. Chandrasekaran.

The Assistant Controller's decision was based on the fact that imatinib mesylate was not `new' (having been `anticipated' from a 1992 patent application covering the imatinib base).

Novartis' case for a patent rests on its claim that the substance in the form in which it has been developed has better capability (30 per cent) for absorption in the human tissue. The Patent Office holds this as not amounting to "increased efficacy" over the earlier known forms of imatinib and, hence, non-patentable, Mr Praveen Raj said. A definition for `efficacy' is not found in any other patent statute in the world. Novartis had also asked the High Court to declare Section 3(d) of the Patents Amendment Act, 1970, as amended in 2005, unconstitutional and in breach of India's obligation under the TRIPS agreement.